High temperature detonator

ABSTRACT

A high temperature or radiation resistant exploding bridge wire detonator having an azo-bishexanitrobiphenyl explosive charge positioned adjacent the exploding bridge wire.

0 United States Patent [151 3,659,527

Abegg et al. 1 May 2, 1972 [54] HIGH TEMPERATURE DETONATOR I ited [72]Inventors: Moroni Taylor Abegg; William B. Leslie, [56] Re c both ofAlbuquerque, N. Mex. UNITED STATES PATENTS [73] Assignee: The UnitedStates of America as 3,158,098 11/1964 Reithel ..102/28 EB representedby the United States Atomic Energy Commission Primary Exammer-Verlm R.Pendegrass [22] F] d O t 29 1970 Attorney-Roland A, Anderson re c 211Appl. No.: 85,072 [573 ABSTRACT A high temperature or radiationresistant exploding bridge wire detonator having anazo-bishexanitrobiphenyl explosive charge positioned adjacent theexploding bridge wire n c [58] Field of Search 102/28 EB; 149/88 3Claims, 1 Drawing Figure /1 on l I Patented May 2, 1972 3,659,527

INVENTORS MORONI TAYLOR ABEGG WILLIAM B. LESLIE BY HIGH TEMPERATUREDETONATOR BACKGROUND OF INVENTION There are applications wherecomponents and equipment may be subjected to high temperatures orradiation for relatively long periods of time. Such applications mayinclude interplanetary rockets or other space operations exposed tosolar heating, radiation or particles, high speed aircraft, componentswhich may be subject to fire, underground explorations, and the like. Inmany of these applications, it may be desirable to utilize explosivedetonators to initiate an event or perform some useful function, forexample case separation or other cutting function, a protective orsafety function, or the like. When most explosives are subjected to hightemperatures or radiation for significant or even short periods of time,they may be degraded or partially expended to a point where they willfail to properly ignite with detonator speed and force. Some explosiveswhich may survive at elevated temperatures are primary explosives andthus very hazardous to handle and use.

Attempts have been made to overcome these problems by using conventionaldetonators maintained at ambient or reduced temperature by appropriatecooling or insulating means at a location remote from the desiredfunction or task to be performed. The detonator is then used to initiatea length of high-temperature resistant mild detonating fuze and thedetonation front carried by the fuze into the high temperature locationwhere the specific task may be performed. Such arrangements may place anadditional burden on the system by requiring extra cooling or coolingnot otherwise needed and by introducing additional points of possiblefailure into the system.

SUMMARY OF INVENTION It is an object of this invention to provide animproved exploding bridge wire detonator, which may be subjected toelevated temperatures or radiations without being detrimentallyaffected.

Various other objects and advantages will appear from the followingdescription of the invention, and the most novel features will beparticularly pointed out hereinafter in connection with the appendedclaims. It will be understood that various changes in the details,materials and arrangements of the parts, which are herein described andillustrated in order to explain the nature of the invention, may be madeby those skilled in the art.

The invention comprises a high temperature exploding bridge wiredetonator utilizing a thermally stable explosive charge adjacent to theexploding bridge wire.

DESCRIPTION OF DRAWING The invention is illustrated in the accompanyingdrawing of a cross-sectional view of a bridge wire detonator of thisinvention.

DETAILED DESCRIPTION Referring to the drawing, the detonator includes abridge wire positioned and supported within a cavity 12 of a detonatorcasing or housing 14 by a wall of the cavity and by a pair of electricalleads or terminal members 16 and 18. Leads l6 and 18 are supported andelectrically insulated from each other by an appropriate plastic, glass,ceramic, or other electrically insulating feedthrough member 20, whichmay be threaded or otherwise secured within cavity 12 of a casing 14.Bridge wire 10 is at least partially embedded in or otherwise positionedin intimate contact with explosive column 30. Explosive column 30 is apellet or mass of azo-bishexanitrobiphenyl explosive at a density offrom about 0.6 to 1.3 grams per cubic centimeter which may be preformedand inserted in cavity 12 or pressed directly into cavit';- 12 byappropriate means. An additional explosive or a fuze or the like (notshown) may be positioned adjacent explosive column 30 m cavity 12 toperform some desired task or to increase the ef- OzN- In one instanceazo-bishexanitrobiphenyl powder was pressed into the cavity of anexploding bridge wire detonator against a 0.0015 inch diameter by 0.060inch long gold bridge wire. Explosive column 30 was 0.22 inches indiameter by 0.30 inches long at a density of 0.80 grams per cubiccentimeter. When the detonator was heated in an oven at 530 F andmaintained at that temperature for 2.5 hours, the detonator was fired bya capacitor charged to 1,500 volts while still at the 530 F temperature.The detonator initiated a length of flexible linear shape chargecontaining the explosive hexanitrostilbene.

Azo-bishexanitrobiphenyl exploding bridge wire detonators were initiatedat room temperature with firing voltages of from about 2 to 4 kilovoltsand resulted in an average function time of about 3.35 microseconds.There is a wide range of values for explosive bulk density (such as 0.6to 1.3 grams per cubic centimeter), bridge wire size and material, andexplosive column dimension that may be used successfully with thisexplosive. This explosive may be detonated at temperatures as high as750 F.

What is claimed is:

1, A detonator for use at temperatures to about 750 F comprising adetonator casing having a cavity for an explosive material,azobishexanitrobiphenyl explosive within said cavity, and an explodablebridge wire positioned against said explosive.

2. The detonator of claim 1 wherein said explosive is at a density fromabout 0.6 to 1.3 grams per cubic centimeter.

3. The detonator of claim I wherein said bridge wire is gold and saidexplosive is ignitable at a voltage of about 1,500 volts.

1. A detonator for use at temperatures to about 750* F comprising adetonator casing having a cavity for an explosive material,azo-bishexanitrobiphenyl explosive within said cavity, and an explodablebridge wire positioned against said explosive.
 2. The detonator of claim1 wherein said explosive is at a density from about 0.6 to 1.3 grams percubic centimeter.
 3. The detonator of claim 1 wherein said bridge wireis gold and said explosive is ignitable at a voltage of about 1,500volts.